Power bending machine for dies



Feb 9, 1954 s. LESKIEWICZ ET AL 2,668,571

POWER BENDING MACHINE FOR DIES 4 Sheets-Sheet 1 Filed April 21, 1949 .IIIIIIIIIIIIIIIYIIIIIIII 1954 s. L ESKIEWICZ ETAL POWER BENDING MACHINE FOR DIES 4 Sheets-Sheet 2 Filed April 21, 1949 4 Sheets-Sheet 3 s. LESKLEWICZ ErAL POWER BENDING MACHINE FOR DIES Feb. 9, 1954 Filed April 21, 1949 1954 s. LESKIEWICZ ETAL POWER BENDING MACHINE FOR DIES 4 Sheets-Sheet 4 Filed April 21, 1949 Q M w em w mm, (A

Patented Feb. 9, 1954 UNITED STATES PATENT OFFICE POWER BENDING MACHINE FOR DIES Application April 21, 1949, Serial No. 88,816

7 Claims.

This invention relates to a power bending machine for shaping metal stock, such as used in making shoe dies, paper cutting dies, millinery dies and the like. By way of illustration, in the shoe industry, dies are commonly used for cutting out shoe parts, such as soles, innersoles, uppers, Vamps, quarters and the like. These shoe parts are commonly cut by dies of varying size and height, shaped to make the proper out. 80- -called clicker dies are ordinarily made from a strip of cold and hot rolled steel from about /8 to inch thick and from n inch to 1% inches high, and these are normally formed on hand operated bending machines which bend the die stock to the desired shape in conformity with a pattern which is provided. So-called handle dies are made from similar stock but are ordinarily higher, and range from 1% to 2% inches in height. So-called walker dies, however, for cutting out heavy or thick pieces of leather, rubher and other composition materials, such as are used in making outer soles for shoes, are made from very heavy hot rolled steel from about to 3% inch thick and from 1 inch to 6 inches in height. These heavy walker dies at the present time are made by hand forging, whereby a blacksmith heats the die stock in a forge to red heat and forms the die by bending it over an anvil with a hammer. One such die an hour, and eight a day, is the average production of a skilled operator by the hand forging process.

The hand-operated bending machine for dies is, of course, not strong enough for bending heavy dies such as walker dies, and which in the past have been made from hot rolled steel, as stated. Attempts have been made in the past to develop a power bending machine for forming heavy dies from cold rolled steel, but great difliculty has been experienced in providing the great force and power necessary, and applying it lightly and gently, as it must be applied to bend a metal die for instance into an evenly curved shape. At the same time means must be provided for varying the point at Which the force is applied to the die stock being shaped. However, we have succeeded in producing such a machine for power bending heavy dies from cold rolled steel, and it is possible in this machine to shape a walker die, for instance, from cold rolled steel, in five minutes in contrast to one hour by the hand-forging process. Production is thus at least 12 times faster, and the machine does not require a skilled operator to run it. The cost of making heavy dies is thus greatly reduced by the use of our machine. 7

Briefly, our machine comprises a suitable frame, a horizontally extending bed on the frame, a fixed forming tool on the bed, a sliding anvil mounted on a movable ram which moves horizontally in very short reciprocating strokes'of great power, means (in this case including an adjustable cam, preferably hydraulically'operated), for extending the length of the ram and hence regulating the space between the forming tool and the movable anvil, and the point at which the force is applied to the object, and means for moving the ram horizontally by short reciprocating strokes (which in this embodiment comprises an eccentric mounted on the main operating shaft). In addition, on the same machine and utilizing the same reciprocating ram we provide an auxiliary bending device forbending lighter fiat die stock edgewise into an arcuate shape, which includes a separate fixed forming tool and movable anvil. This edge bending of fiat die stock is done to provide a tapered or sloping surface vertically for the die stock and to provide enlarged clearance for the cut pieces inside the die and thus prevent clogging of the die when in use.

Before explaining in detail the present invention it is to be understood that the invention is not limited in its application to the details of construction and arrangement of parts illustrated in the accompanying drawings, since the in-- vention is capable of other embodiments and of being practiced or carried out in various ways. Also it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation, and it is not intended to limit the invention claimed herein beyond the requirements of the prior art.

In the drawings:

Fig. 1 is a plan view of our machine;

Fig. 2 is a front end elevation;

Fig. 3 is a side elevation from the left of Figs. 1 and 2;

Fig. 4 isa side elevation of the cam mechanism with the cam partially rotated, and partially in section;

Fig. 5 is a plan view (with a portion in horizontal section, on line 5-5 of Fig. 3) of the auxiliary bending device for bending fiat die stock edgewise;

Fig. 6 is a view similar to Fig. 5 of the auxiliary bending device showing the bending operation;

Fig. 7 is a vertical section on line 1-1 of Fig. 6:

Fig. 8 is a perspective view of a section of large die stock used in walker dies, and

Fig. 9 is a perspective view of a section of smaller die stock used in making clicker dies.

In the drawings, 10 represents the frame of the machine and includes legs I l and thehorizontal top or bed [2. Rigidly mounted on the frame of the machine is a fixed forming tool [5 and the anvil support includes clamping bracket l6, vertical supports l1, bolts l8 and nut IS. A ram 20 is mounted in the bed l2 of the machine for horizontal, reciprocating movement therein andcarries the sliding anvil 22- fixedly mounted on. the front end of the ram 21!; Asseen..more particularly in Fig. 1, the forming I5 is eggor pear-shaped in cross section, having a rounded front portion 15a. The sliding anvil 22- in turn is fork-shaped in cross-section having arm portions 22a, which extend around the sides of, and span the rounded central portion l5a of the fixedforming tool,

The means for moving the 'ram- 24 in a horizontal-reciprocating movement. includes the rockor arm" 25 having a cylindrical. top portion 26 fitted: in a complementary groove in the under of the ram 2 9-. At its bottom end rocker 25 ismounte'd for oscillating movement about a horizontal. pivot 28- mounted in bracket 29 and suitably bolted to the frame ofthe machine, as by bolts Ill] (Fig. 3); A driving arm 35 is mounted on the frame of the machine for horizontal reciprocating movement beneath the horizontal ram 21]- and: at its front end carries a bifurcated bracket 36 having fingers 35o which extend around the two sides of rocker arm '25 and carry horizontal shaft 3-1 passing through rocker arm 25 and. on which rocker arm 25 .is pivoted for oscillating movement.

The driving shaft M] is mounted in suitable bearings -42 and carries thereon an eccentric 45", which. rotates in the bearing. box. 45 which forms the rear parts of driving arm 35. The eccentric A5 has an accentricity of .080- inch, and the main driving shaft is a variable speed device which rotates shaft 40 from 56 to 300 revolutions per minute, and the result is that driving arm-35, ram 2!? and sliding. anvil 22 are thus given a" reciprocating horizontal movement of 5680' inch from 50 to 309 times per minute, whereby a rapid series of short blows of great force are imparted to the: die stock 2' 3 as shown in. Fig. 3). A coil spring EB, attached to the frame 11! of the machineat one end and to a hook it on the rear endlof ram Zll, serves to keep rain 28 inc retracted position at all times.

' Means are also provided. for extending the l'ength'nf driving arm 35 and hence the position of sliding anvil 22 and ram 25: with respect to eccentric 45,, for the purpose of regulating the space between themovable anvil 22 and the terming tool 15, andhence the point at which the force is applied to th piece of die stock. 24,, or other object being bent. This means comprises cam means 59 (shown in Figs. 3 and 4),. which includes cam members 50a and having inclined abutting cam surfaces Ela and 5|b which are slidably rotated with respect to one another and carry horizontal edge stops 52a and 52b respectively. Cam member 59a is fixedly mounted on shaft 54, in turn mounted in driving arm 35, by means of pin: 5'5. Cam member 58b in turn is rotatably mounted on fixed shaft 5 being fixed to pinion 56 by means of pins 5'! and arranged to travel on transverse horizontal rack 58. Rack 58 is caused to traverse the machillc ZlQZ'i QZI E S and transversely by arm 59 fixedly attached thereto at its top end, and which arm 59 is attached at its other end to the rod 6| of a double acting hydraulic cylinder Bl] suitably mounted on the frame It. Flexible connections 62 (Fig. 3) run to a valve and sump 5-3; As the hydraulic cylinder ED is a standard device in all respects its construction need not be described in detail. The valve control 63, also of standard construction which may be operated by hand or from a foot treadle, such as 64, controls the action of hydraulic cylinder 6B3 As will be understood from the construction, the distance between the movableanvil 22? and: th forming tool 15, and hence thepointat which the bending force is applied to the diestock 2% or other object being shaped, is deternnmd; by the regulating valve 63 which through arm 59 moves the rack 58 to the right (as shown in Fig. 2), which rotates the pinion 56 in a counterclockwise direction and hence opens the camimembers 56a and 5927-; as: shown Fig. 4. This thus extends: the length of driving. arm 35, andmoves forward. the starting position oc'slicb ing anvil 2 2 with respect. to the forming tool. t5.

Means for drivingarm 3 5:inreciprocating horizontal movement is provided, which. includes a source of power; such as an electric motor (not shown); which by a sprocket chain (not shown) drives sprocket wheel t1.- mounted on the-horizontal driving shaft -49. Sui-table switches or controls, or course; are provided for regulating the speed of the electric motor which bemg or standard construction, need notzbe described in detail. In operation, it will be understood that the piece of heavy di stock 24 (separately shown in Fig. 8), which 'isa straight: flat strip of steel-,has atemplate or pattern-. 65 of. the desired shoe part shape clamped to it at rightangles, as shown more particularly in Fig. 2f a. suitable clamping tool 66. A suitable clampmg tool (as shown in Figs. 1 and 2)., is that disclosed .Leskiew-icz Patent .No. 2,446,773, granted August 19:, i948. The strip of die stock 23- is then placed: vertically between. the rorming tool '15 and sliding anvil 2.2 anda switch or clutch not shown) is then thrown in to operate the machine. This causes the sliding anvil 22 toreciprocate rapidly in strokes; of .080 of an inch in length and from to Shdtimes per minute, and the arm portions 222aof the sliding anvil. 22 thus bend and shape the die stock around the rounded front-end l-5a of the forming tool 45. The amount of the bending done to the die stock of course, determined by the template 65 held adjacent to the die stock 34 by the clamping. tool 66, previously referred to. Particularly at the start it is necessary for the sliding anvil to be close to the: forming tool and: this spacing,:as previously statedis controlled through the regulating valve 63. As each portion of the die stock is bent to the desired shape the stock "24 is advanced through the anvil and given the proper bend until the entire pieceis bent asshow-n in Fig. i. This operation takes about fiveminutes in this machine.

On. the same machine, and. utilizing the sa reciprocating ram 2d, we provide an additional, auxiliary bending device for bending lighter flat die stock edgewise intoan arouate shape as shown Figs- 1., 2 and 3- and more detail in Figs. 5, 6 and '7. The purpose oi this auxiliary bending device is to bend a lighter piece of die stock HI (Fig. 9) from a flat to an. arcuate shape edgewise, and thus 'to provide a tapering clearance the finished die,v which: will permit the Work pieces to be cleared from the die without clogging. The fixed forming tool 12 includesa pair of abutting members 13 pivoted on verticalpivots 14 and having a transverse horizontal groove 13a therein (Fig. 3) Abutting members 13 are rigidly supported except for pivotal movement on stationary bed l2 by bracket 12a. A moving anvil 15 having overhanging flange I5 is rigidly mounted on the top surface of the reciprocating ram (Fig. 3). The auxiliary bending deviceis operated by placing a section of die stock in (Figs. 9 and 6) flatwise between the forming tool 12 and the movable anvil l5, and causing the reciprocating ram to push the movable anvil 15 and die stock ii! against the abutting members 13. The abutting members 13 yield pivotally as shown in Fig. 6 and a bending force is thus applied to the die stock 10 causing it to bend edgewise into an armate shape as shown in Fig. 6.

It will thus be seen that we have provided a power bending machine for forming heavy dies from fiat strip, cold rolled steel, with means on the same machine for additionally bending lighter flat die stock edgewise into an arcuate shape. Our machine thus greatly reduces the cost of making such dies.

We claim:

1. In a power bending machine, a frame, a horizontally extending bed on the frame, a forming tool fixed on the bed, a ram movable horizonally within said bed, an anvil mounted on said ram to cooperate with said forming tool, and means for varying the starting position of said anvil with respect to said forming tool, including cam members having abutting inclined surfaces, means including a rack and pinion and a hydraulic cylinder for rotating one cam member relatively to the other on said abutting inclined surfaces, and power means for moving said ram and anvil thereon against said forming tool in short reciprocating strokes, for bending metal stock placed between said anvil and forming tool.

2. In a power bending machine, a frame, a horizontally extending bed on the frame, a forming tool fixed on the bed, a ram movable horizontally within said bed, an anvil mounted on said ram to cooperate with said forming tool, a driving arm mounted beneath said ram, a rocker arm pivotally mounted at its bottom end to a fixed part of the machine and at its top end connecting said driving arm and said ram, a transverse operating shaft, and an eccentric mounted on said shaft, and a source of power for rotating said operating shaft and eccentric mounted thereon for moving said driving arm and anvil thereon against said forming tool in short reciprocating strokes, for bending metal stock placed between said anvil and forming tool.

3. In a power bending machine, a frame, a horizontally extending bed on the frame, a forming tool fixed on the bed, a ram movable horizontally within said bed, an anvil mounted on said ram to cooperate with said forming tool, and means for varying the starting position of said anvil with respect to said forming tool, including cam members having abutting inclined surfaces, and means for rotating one cam member relatively to the other on said abutting inclined surfaces, a driving arm mounted beneath said ram, a rocker arm pivotally mounted on its bottom end to a fixed part of the machine and at its top end connecting said driving arm and said ram, a transverse operating shaft, and an eccentric mounted on said shaft, and a source of power for rotating said operating shaft and eccentric mounted thereon for moving said driving arm, and hence the ram and anvil thereon against said forming tool in short reciprocating strokes, for bending metal stock placed between said anvil and forming tool.

4. In a power bending machine, a frame,

horizontally extending bed on the frame, a forming tool fixed on the bed, a ram movable horizontally within said bed, an anvil mounted on said ram to cooperate with said forming tool, and means for varying the starting position of said anvil with respect to said forming tool, including cam members having abutting inclined surfaces, means including a rack and pinion and a hydraulic cylinder for rotating one cam member relatively to the other on said abutting inclined surfaces, at driving arm mounted beneath said ram, a rocker arm pivotally mounted on its bottom end to a fixed part of the machine and at its top end connecting said driving arm and said ram, a transverse operating shaft, and an eccentric mounted on said shaft, and a source of power for rotating said operating shaft and eccentric mounted thereon for moving said driving arm, and hence the ram and anvil thereon against said forming tool in short reciprocating strokes, for bending metal stock placed between said anvil and forming tool.

5. In a power bending machine, a frame, a horizontally extending bed on the frame, a forming tool fixed on the bed, a ram movable horizontally within said bed, an anvil mounted on said ram to cooperate with said forming tool, ram actuating means including a driving arm and a rocker arm engaging said ram, means for varying the starting position of said anvil with respect to said forming tool including cam members having abutting inclined surfaces and means for rotating one cam member relatively to the other on said abutting inclined surfaces, a transverse operating shaft, an eccentric mounted on said shaft and a source of power for rotating said operating shaft and eccentric thereon for moving said driving arm and rocker arm and hence the ram and anvil thereon against said forming tool in short reciprocating strokes, for bending metal stock placed between said anvil and forming tool.

6. In a power bending machine, a frame, a horizontally extending bed on the frame, a forming tool fixed on the bed, a ram movable horizontally within said bed, an anvil mounted on said ram to cooperate with said forming tool, means for varying the starting position of said anvil with respect to said forming tool, including cam members having abutting inclined surfaces and means for rotating one cam member relatively to the other on said abutting inclined surfaces, ram actuating means including a driving arm mounted beneath said ram, a rocker arm pivotally mounted at its bottom end to a fixed part of the machine and it its top end connecting said driving arm to said ram, a transverse operating shaft, an eccentric mounted on said shaft, and a source of power for rotating said operating shaft and eccentric mounted thereon for moving said driving arm and hence the ram and anvil thereon against said forming tool in short reciprocating strokes, for bending metal stock placed between said anvil and forming tool.

7. In a power bending machine, a frame, a horizontally extending bed on the frame, a form ing tool fixed on the bed, a ram movable horizontally within said bed, an anvil mounted on mm to; cooperate.- with saint tor-111mg; $001, means: for namin starting; position of. said wtthrespeet to saicL .fiorming took inel-edmg earn members having abutting, inclined surfaces and means for rotating one cam member relativeiy to the other on said abutting. inclined surfaces including a rack. and and, a hyd'mzulicv cylinder, :ram actuating means including a driving: arm, mounted beneath said ram, 2. rockerrampivotally' mounted at its bottom end to a; fixed: part: of the machine and. at its top end connecting said driving arm to saidram, 2. transzserse operating shaft, an eccentric mounted on said shaft, and asouree of power for rotating said. operating shaft and eccentric mounted thereon for moving said driving arm and henee: the; ram and anvil thereon against said forming: tool in short reciprocating, strokes, for

Lasxrsiwrcz. FREDERICK A,..

Refierenees Cited the, file :of this patent UNITED STATES Number Numter Name Date Terrell 3, 1864 G ustin t. Mar; 1, 1'88? Eaton Feb. 1', '19'16 Wise v July 8;, I924 Macomber Oct. I6, 1928' Slafter Aug. 19, T930 Leskiewi'cz Apr. "2, 1940 PATENTS Gountry Date Great Britain Mar. 6, 19336 

